Seamless visual object-oriented behavior modeling for distributed software systems

To ease the development of distributed systems, the visual notions for the structural aspects of object-oriented analysis and design should be combined with techniques for handling concurrency and distribution. A novel approach and language for the visual design of distributed software systems is introduced and illustrated by means of an example. The language of OCoNs (Object Coordination Nets) is integrated into the structuring mechanisms of the UML (Unified Modeling Language) standard for object-oriented analysis and design. Such an object-oriented notation is crucial for handling complex software systems and can be extended with the graphical expressive power of Petri nets to also describe concurrency and coordination. The same visual language is used to specify the interfaces and contracts of software components, the resource handling within a component as well as the control flow of services.